Craig earns $2.50 per hour plus $3.50 for each hair cut he gives.
He worked for 7 hours.
In hour basis, he earned
[tex]2.50\times7=17.5[/tex]He gave 4 hair cuts.
For 4 haircuts, he earned
[tex]3.50\times4=14[/tex]So, he total earned
[tex]17.5+14=31.5[/tex]Hence, the correct option is (A).